Subject: Re: MI bus ops(Re: 16bit aligned NS16550 variant)
To: None <email@example.com>
From: None <firstname.lastname@example.org>
Date: 11/09/2001 10:59:46
email@example.com ("Jason R Thorpe") writes:
> I think what I'd really like to see here is for <machine/bus.h> to be
> replaced by:
I pretty much agree completely.
> Included as <machine/bus.h> is now. Defines the
> bus_space_tag_t, bus_dma_tag_t. Each has the
> ops pointers and a void *cookie. If <machine/bus_types.h>
> does not define __BUS_SPACE_MD_CALLS, then it defines
> the macros that actually call the bus_space methods.
> This allows MD code to simply use pointer derefs for
> certain types of space, if it wants to.
> Included by <sys/bus.h>, defines various types that
> <sys/bus.h> needs. Also optionally defines things
> like __BUS_SPACE_FAST_ABI (which might e.g. define
> a faster ABI to be used for bus space methods, such
> as regparm on the x86).
Why should the latter by anything but <machine/bus.h>?
It'll be a bit more of a hassle for conversion, but not that much...